Nurul Aimi Ghazali

Rheological study of nanosilica based drilling fluid

In drilling and well completion operations, drilling fluid is a crucial element as it is employed for the purposes of several functions. The main functions of drilling fluid are to control formation pressure, maintain the wellbore stability, transport the cuttings up to surface to clean the borehole bottom as well as to lubricate and cool the drill bit. Moreover, it is used to minimize the drilling damage to reservoir and suspend cuttings when the pumping is stop, hence it will not falling back down the borehole. The purpose of this study is to formulate new drilling mud formulation modified with nanosilica. Six samples of water based mud (WBM) were prepared using three types of polymers, (Xanthan Gum, Hydro Zan Plus and Hydro Star HT), starch and nanosilica. Basic rheological tests such as density, viscosity and pH were carried out. The density test was carried out using mud balance meanwhile the pH test was using pH meter. The plastic viscosity, yield point and gel strength tests were carried out using viscometer. Besides that, physical observation was also performed for as the stability test. The results concluded that water based mud incorporated with polymer Hydro Zan Plus and nanosilica can be a potential candidate to be commercialized as a smart nanodrilling fluid.

Carbon dioxide (CO2) foam stability dependence on nanoparticle concentration for enhanced oil recovery (EOR)

Foam flooding is an established approach in Enhanced Oil Recovery (EOR) to recover a significant quantity of the residual oil left in the reservoir after primary and secondary recovery. However, foam flooding faces various problems due to low viscosity effect, which reduces its efficiency in recovering oil. Using surfactant to stabilize CO2 foam may reduce mobility and improve areal and vertical sweep efficiency, but the potential weaknesses are such that high surfactant retention in porous media and unstable foam properties under high temperature reservoir conditions. Nanoparticles have higher adhesion energy to the fluid interface, which potentially stabilize longer lasting foams. Thus, this paper is aimed to investigate the CO2 foam stability and mobility characteristics at different concentration of nanosilica, brine and surfactant. Foam generator has been used to generate CO2 foam and analyze its stability under varying nanosilica concentration from 100 - 5000 ppm, while brine salinity and surfactant concentration ranging from 0 to 2.0 wt% NaCl and 0 – 10000 ppm, respectively. Foam stability was investigated through observation of the foam bubble size and the reduction of foam height inside the observation tube. The mobility was reduced as the concentration of nanosilica increased with the presence of surfactant. After 150 minutes of observation, the generated foam height reduced by 10%. Liquid with the presence of both silica nanoparticles and surfactant generated more stable foam with lower mobility. It can be concluded that the increase in concentration of nanosilica and addition of surfactant provided significant effects on the foam stability and mobility, which could enhance oil recovery.

Nanoemulsion Applications in Enhanced Oil Recovery and Wellbore Cleaning: An Overview

This article is an overview of potential applications of nanoemulsion as a promising candidates for enhanced oil recovery (EOR) and as a medium for wellbore cleaning. Nanoemulsion is an emulsion that has nanosize particle distributions in the range of below 500 nm. It also has lower interfacial tension (IFT) as low as the value of 0.001 mN/m. The small particle size distributions in nanoemulsion resulted the good properties of nanoemulsion in term of large surface area. This excellent property will improve the sweeping efficiency of the oil droplet in the reservoir and finally increase the oil recovery. Besides that, the unique features possess by nanoemulsion make it suitable as superior wellbore cleaner as compared to conventional detergent-based cleaner. Thus, the significance of nanoemulsion becomes the major highlight in oil and gas industry. This overview on nanoemulsion applications is imperative and necessary in order to provide an insight for the future development and perhaps open a door to extend the applications of nanoemulsion to other more challenging areas.

Potential of Corn Starch as Fluid Loss Control Agent in Drilling Mud

Fluid loss can be defined as the lost of mud filtrate into a porous permeable formation due to high hydrostatic pressure compared to the formation pressure. This phenomenon may cause some major problems to the workover operation such as formation damage, stuck pipe, and poor cementing job. Thus, in order to prevent fluid loss into formation, an environmentally safe, non-toxic, high biodegradability and low cost of polymer additive in drilling mud was prepared from corn starch as the fluid loss control agent. The purpose of this study is to investigate the potential of utilizing natural polymer-corn starch acting as fluid loss control agents in water-based drilling mud. The filtration and rheological properties of the water-based mud were analyzed at 170 to 200 °F temperature range with 0 to 10 g of corn starch concentration. Experimental results showed that the higher concentration of corn starch gave better fluid loss control behavior. Therefore, there is high potential of corn starch to be used as fluid loss control agent in drilling mud.

Effective Bridging Agent Particle Sizes of Reservoir Drilling Mud

The optimization of bridging agent size selection in drilling mud is now critically demanding due to the desired pressure to produce the non-damaging fluid or low damaging fluid. Bridging agent is the materials that can give effect on minimizing fluid invasion and optimize the sealing operations. Three different sizes of bridging agents were prepared, Fine (F), Medium (M) and Coarse (C) size where calcium carbonates had been selected as the bridging agents. Water Based Mud had been chosen as based of drilling mud to be investigated. Experiments conducted were rheology and filtration test. The study shows that the mud weight was increase with increasing size of bridging agent. The filtration test showed a high fluid loss in mud samples without bridging agent (Mud A) and least fluid loss in Mud B. Thus, the fine size of bridging agent can form better filter cake and prevent the fluid being loss too much thus reducing the damage to the reservoir wellbore.

Carbon Dioxide Separation Using Amine Modified Zeolite in Pressure Swing Adsorption System

Carbon dioxide (CO2) removal from natural gas attracts more attention than other impurities due to its corrosiveness property and it also possess no heating value in the sales natural gas. Amine based chemical absorption has been used commercially for CO2 separation in gas processing plant. However, the liquid amine based processes pose operating difficulties due to high regeneration energy, large equipments size and solvent leakage. This research studies modification of porous materials, zeolite NaY by grafting amine functional group using monoethanolamine directly to the surface of the solid sorbents. The structures and physical properties of amine modified adsorbent were characterized using powder X-Ray Diffraction (XRD), nitrogen adsorption at 77K and thermogravimetric analysis. Since application of Pressure Swing Adsorption (PSA) has been widely used in various plants in the world, this research was extended to study carbon dioxide separation using amine modified adsorbents in PSA experimental system. Effects of adsorption and regeneration behaviour on CO2 separation were investigated. Amine modified NaY showed better result compared to unmodified NaY in term of improvement in physical and chemical properties, high CO2 adsorption capacity and modified adsorbents were ease of regeneration.

Extracted Lignin from Rhizophora’s Black Liquor as Fluid Loss Control Additive in Water Based Drilling Mud

The ability of lignin from Rhizophora Apiculata’s black liquor to act as a fluid loss additive in water-based drilling at HTHP condition was investigated. The lignin biopolymer was extracted from the black liquor using acid precipitation technique using 20% by volume of sulphuric acid at temperature of 45°C and 60°C for pH 4, 6 and 8 respectively. The produced lignin was tested in water based drilling mud at temperature of 250°F, 300°F,350°F and 400°F . The optimum extraction parameters showed that the highest yield of lignin extraction of approximately 51.2% was obtained at pH 4 and extraction temperature of 45°C. It was also observed that the Rhizophora Apiculata’s lignin has remarkable rheological and filtration controlling properties at HTHP condition as compared to the commercial lignin additive.

Solubility Determination of Tamarind Seeds Extracts by Using Supercritical CO2 Extraction

In recent years, tamarind seeds extracts are used widely in food, pharmaceutical and textile industry due to unique functions as cooking oil, antibacterial and thickening agent. In this study, a simple static technique is used to obtain the solubility of tamarind seed in supercritical carbon dioxide because there is no study on that yet. The solubility measured is performed at temperatures and pressures ranging from 40oC, 60oC, 80oC and 3000psi, 5000psi and 7000psi respectively; resulting in mass fractions in the 6.00 x 10-8 to 5.84 x 10-7 range. The Chrastil model is used to correlate the experimental data. The oil yield extract in range of 0.0375 to 0.365g.

Kinetic Mechanism on Synthesis of Copper Nanoparticle from Reduction Reaction - Effect of Temperature

Copper nanoparticles, due to their interesting properties, low cost preparation and many potential applications in catalysis, cooling fluid or conductive inks, have attracted a lot of interest in recent years. In this study, copper nanoparticles were synthesized through the palm leaves extract that act as reducing agent. In this synthesis route, the hydroxyl groups of the polyphenols in palm extract are capable to act as reducing agent for reduction reaction. The effect of temperature given starting with control parameters at room temperature proceeds to 40, 50, 60, 70 and 80°C with the time length of 2 hours and 10 milimol copper nitrate aqueous solution. Characterization had been conducted using the instrument of UV-vis spectrophotometer, FTIR and ESEM. The average size of all powder nanoparticles was found to 109, 86, 196, 133, 241, and 230nm accordingly from room temperature till 80°C. The correspondence analysis of the results yielded that the optimum temperature was at 40°C which is 86nm of average copper nanoparticle size.

The Effects of Temperature on Rheology Properties and Filtrate after Using Lemongrass as Lost Circulation Materials for Oil Based Drilling Mud

Lost circulation materials (LCM) are used to combat mud loss to the reservoir formation which can cause problems during drilling operation. Difficulties in handling and costly are those challenges faced by drilling operator. Mostly LCM can work better in water based mud compared to oil based mud due to characteristic of LCM itself. Nowadays, most of operator interested in the ultra-deep water due to the limitation of reservesand deals with high temperature and high pressure conditions.Oil based mud (OBM) is more preferable in high temperature conditions compared to water based mud hence a laboratory study was carried out to investigate the effect of temperature on the performance of lemongrass with different sizes in oil based mud. The oil based mud was formulated and tested with three different temperatures which are 250oF, 275oF and 350oF. The lemongrass LCM was prepared with three different sizes which are 150 microns, 250 microns and 500 microns. The sizes distribution of LCM is one of the main contributors to the success of LCM in the formation. The oil based mud samples were tested using Fann Viscometer to determine rheology properties and HPHT Filter Press to investigate the amount of filtrate. It was found that different temperatures and sizes have great effects on the lemongrass LCM in the oil based mud. The optimum temperature for lemongrass LCM is 275oF and with the sizes of 250 microns.